The present invention relates to an improved gas-blast circuit breaker of the type disclosed in Swiss Patent Application 4015/84-0. More particularly, the present invention relates to a circuit breaker having a housing which is filled with insulating gas and in which two contact members are arranged which are moveable relative to each other along an axis and in each case have one arcing and one rated-current contact. In this circuit breaker, the overall length extending in the direction of movement of the contact members is kept small by the fact that electric connections are provided which are carried into the housing transversely to this direction of movement and which form loops in the interior of the housing. However, circuit breakers of this type need a comparatively large driving energy on disconnection since rated-current and arcing contacts are moved at the same time.